Concrete mixing equipment and dispensing attachment therefor



June 21, 1966 H. M. ZIMMERMAN I 3,257,102

CONCRETE MIXING EQUIPMENT AND DISPENSING ATTACHMENT THEREFOR Filed April 50, 1964 6 Sheets-Sheet l Harold M. Zimmerman INVENTQR.

ATTORNEYS June 21, 1966 H. M. ZIMMERMAN 0 CONCRETE MIXING EQUIPMENT AND DISPENSING ATTACHMENT THEREFOR 6 Sheets-Sheet 2 Filed April 30, 1964 iif ovw /M 1H1! C N? m new 9% VNV Harold M. Zimmerman ATTORNEYS J1me 1966 H. M. ZIMMERMAN 3,

CONCRETE MIXING EQUIPMENT AND DISPENSING ATTACHMENT THEREFOR Filed April 50, 1964 6 Sheets-Sheet .3

Fig. 3

a a/a M.

Zimmerman INVENTQRS W aq ATTORNEYS June 21, 1966 H. M. ZIMMERMAN 3,257,102

CONCRETE MIXING EQUIPMENT AND DISPENSING ATTACHMENT THEREFOR Filed April 30, 1964 6 Sheets-Sheet 4 .I' 34 N WW )I W IHH I L -zip] h Fig. H 260 Harold M Zimmerman INVENTOR ATTORNEYS '1 June 21,1936

H. M. ZIMMER CONCRETE MIXIN MAN G" EQUIPMENT AND DISPENSING ATTACHMENT THEREFOR 6 Sheets-Sheet 5 Filed April 30, 1964 III lllllll ll, 6

. 4:555. vwiiiEEi.

Harold M Zimmerman INVENTOR. BYM

ATTORNEYS June 21, 1966 H. M. ZIMMERMAN 3,257,102

CONCRETE MIXING EQUIPMENT AND DISPENSING ATTACHMENT THEREFOR Filed April 30, 1964 6 Sheets-Sheet 6 1| Harold M. Zimmerman INVENTORS ATTORNEYS United States Patent 3,257,102 CONCRETE MIXING EQUIPMENT AND DIS- PENSING ATTACHMENT THEREFOR Harold M. Zimmerman, RD. 1, Ephrata, Pa.

Filed Apr. 30, 1964, Ser. No. 363,953

37 Claims. ((11. 259151) This invention relates to concrete mixing equipment which combines and mixes ingredients to form and deliver concrete and more particularly it relates to an attachment for such equipment to render the equipment capable of mixing concrete and dispensing the same by gravity or under pressure and for performing such dispensing to a location adjacent to the equipment or quite remote therefrom. n v

In the conventional form of concrete mixing equipment, a rotatable mixing drum is mounted upon a truck bed and is provided with an opening for receiving the ingredients to form the cement or concrete. When such ingredients are received, the drum is rotated about its axis to mix the concrete to a usable condition, and when the truck reaches its desired destination, an outlet opening at the discharge end of the drum is uncovered to permit the mixed concrete to discharge by gravity into a bucket means or into a suitable open trough which transports the concrete to the mold or form into which it is subsequently poured.

While such conventional gravity discharge equipment is satisfactory for use when the mixed concrete is to be poured adjacent to or. in the immediate vicinity of the truck, it is cumbersome and ineflicient to use when the concrete is to be used at a location quite remote from the truck. For instance, it may be desirable to pour concrete at a location which is inaccessible to the truck. Such a location could be several stories above or below ground level or could be spaced horizontally along the ground for some distance from the truck. In either event, the cement could only be transported to the location by using complicated interfitting trough sections or by pouring the concrete into buckets or wheelbarrows which are then transported individually to the location. Naturally, neither of these alternatives is completely acceptable for commercial practice and it is therefore desirable to provide some means for satisfactorily conveying the mixed concrete to a location quite remote from the truck.

It has been found that by utilizing pressurized air, the mixed concrete can be suitably transported over large distances and supplied to remote sources which are spaced away from the truck. The distances can be either in the horizontal direction, or the vertical direction, or both. To form the fluid conveyor for delivering the mixed concrete under pressure, it is necessary to provide a conduit means and an attachment for afiixing such a conduit means to the concrete mixing truck. However, it is not sufiicient to merely modify a conventional ready-mix concrete truck by converting it into apressure discharge mixer, since such amodified unit would be incapable of conventional or gravity discharge operation. It will be seen then that in order to provide a completely adaptable mixing apparatus, such apparatus must be capable of mixing concrete and delivering it either in the conventional manner or under pressure and over substantial distances.

In order to provide an attachment which forms an integral part of the concrete mixing equipment, yet meets the necessary adaptability requirements by permitting both conventional discharge and pressurized long distance discharge, it is necessary to provide means for disengaging or otherwise rendering inoperative the pressurized portionof the attachment when gravity flow is desired, and vice versa. Furthermore, there are numerous other considerations which arise in relation to providing an attachment 1 for a rotatable concrete mixing drum. Unless the attach- 3,257,102 Patented June 21, 1966 ment is to rotate along with the drum, which is highly unlikely, some means must be provided for permitting relative rotation between the drum and its attachment. Also, knowing the propensity of mixed concrete to harden or solidify, some suitable means must be provided for cleaning and/ or flushing the equipment in order to prevent any concrete therein from hardening and rendering any or all of the parts of the equipment inoperative. Moreover, it is important to provide some means for visually indicating to the operator of such mixing equipment, the feed rate or fiow rate of the mixed concrete being dispensed. During normal or conventional gravity dispensing, no such problem arises since the operator can see the mixed concrete being dispensed, but during pressurized dispensing, the concrete is often discharged a substantial distance away from the mixing equipment and the operator is therefore unable to see the concrete discharging, so he cannot properly vary the flow rate unless some means is provided for permitting visual inspection within the equipment.

With the foregoing in mind, it is, therefore, a primary object of the present invention to provide concrete mixing equipment which can deliver mixed concrete by gravity discharge or by pressurized discharge over substantial distances to a point remote from the mixing equipment.

Another primary object of the present invention is to provide an attachment which can be readily secured to a conventional concrete mixing truck to dispense the mixed concrete therefrom through a conduit means under the infiuence of pressurized air, and to provide means for disengaging or otherwise suitably disabling at least a portion of the attachment to permit conventional gravity dispensing of the mixed concrete.

Further general, though equally significant, objects of the present invention include the provision of a concrete mixing truck attachment which: (a) can be easily cleaned or flushed to prevent any cement from hardening therein; (b) permits relative rotation of the mixing drum on the truck; (c) allows visual internal examination during operation to facilitate adjustment of the mixed concrete flow rate; (d) provides both the inlet for introducing concrete ingredients into the mixing drum and the outlet for discharging the mixed concrete therefrom; (e) can be eifectively sealed to build up and maintainair pressure within the mixing drum; (f) has a conduit means thereon for long distance pressurized transfer of the mixed concrete, but is constructed to permit removal of the conduit means for conventional gravity discharge of themixed concrete; (g) can be easily and quickly operated and manipulated by a normally skilled operator; and (h) is durable, inexpensive, and relatively simple toinstall or remove.

Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in connection with the annexed drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

FIGURES 1 and 2. are, respectively, rear and side perspective views in accordance with the principles of the present invention showing a concrete mixing truck having a dispensing attachment affixed thereto;

FIGURE 3 is a fragmentary side elevational view of the concrete mixing equipment of the present invention;

FIGURE 4 is a fragmentary rear elevational view, partly in section, of the concrete mixing equipment shown in FIGURE 3;

FIGURE 5 is a sectional view taken substantially along line 55 of FIGUREA;

FIGURE 6 is a fragmentary side elevational view of one form of roller means utilized in equipment of the present invention;

FIGURE 7 is a sectional view taken substantially along line 7-7 of FIGURE 6;

FIGURE 8 is a fragmentary side elevational view of another form of roller means utilized in the equipment of the present invention;

FIGURE 9 is a sectional view taken substantially along line 9-9 of FIGURE 8;

FIGURE 10 is a fragmentary side elevational view of another form of roller means utilized in the equipment of the present invention;

FIGURE 11 is a sectional view taken substantially along line 11-11 of FIGURE 10;

FIGURE 12 is a top plan view of the supporting frame which mounts the attachment of the present invention;

FIGURE 13 is a sectional view taken substantially along line 13-13 of FIGURE 12;

FIGURE 14 is a sectional view taken substantially along line 14-14 of FIGURE 12;

FIGURE 15 is a sectional view taken substantially along line 1515 of FIGURE 12;

FIGURE 16 is a rear elevational view of the attachment of the present invention with the conduit means disassembled therefrom; and

FIGURES 17 and 18 are schematic views of the outlet valve means on the attachment'in both its open and its closed positions.

In accordance with the principles of the present invention and as can be seen generally from FIGURES 1 and 2 thereof, there is provided a concrete mixing equipment including a conventional ready-mix concrete truck generally designated 1 and having aflixed thereto a housing generally designated 2, a hopper chute generally designated 3, a supporting frame generally designated 4, a means generally designated 6 for mounting the housing 2 on a rotatable mixing drum generally designated 8 which forms a part of the truck 1, and a discharge means generally designated 10.

The attachment of the instant invention, which can be readily coupled to the ready-mix truck 1, includes basically the housing 2, the hopper chute 3 and the discharge means It). The supporting frame 4 serves to movably mount the attachment for assembly with the mixing drum 8 on the truck 1. The means 6 serves to sealingly interconnect the attachment to the drum, yet to permit relative rotation between the attachment and the drum.

As can be best seen from FIGURE 2, the mixing drum 8 is disposed upon the bed of the truck 1 and gradually tapers to an outlet or discharge end located at the rear end of the truck bed. As is conventional, the drum is mounted for rotation about its own axis to accomplish the desired mixing of the cement. To this end, a gear may be attached to or formed about the periphery of the drum to mate with a driving gear affixed to a reversible motor. Thus, depending upon the operational direction of the driving motor, the drum 8 may be rotated in either a clockwise or a counter-clockwise direction about its central axis.

At its outlet end, the drum 8 is provided with a terminal or peripheral ring flange 12, as shown in FIGURES 5 and 7. The attachment is secured to this ring flange 12 -by the means 6 which includes a hub generally designated 14 and having a base wall 16 and an outwardly extending annulus or inner ring 18. The base wall 16 is secured to the terminal ring flange 12 by any suitable means such as bolts 26 The periphery or edge of the base wall 16 projects beyond that of the ring flange 12.

The attachment is sealingly secured to the drum 8 by the means 6 and more precisely by a portion of the means 6 generally designated 22 and cooperative with the hub 14 to affix the housing 2 thereto. The sealing means 22, as can best be seen in FIGURES 7 and 9, includes a ring 24 which is recessed as at 26 to receive a sealing O-ring 28. The ring 24 is coupled to the front wall 29 of the housing 2 by an extension 30 which itself cooperates with an upstanding flange 32 to receive a further sealing O-ring 34; The O-ring 28 effects the seal with the base wall 16 of the hub 14 whereas the O-ring 34 effects the seal with the ring 18 of the hub 14. The seal formed by the O-ri-ng 34 is essentially a dirt seal so as to prevent undesired material from passing between the ring 18 and the ring 24 to contaminate the O-ring 28. On the other hand, the primary function of the O-ring 28 is to effectively provide a pressure seal between the housing 2 and the interior of the tank 8. Preferably, the area between the seal 34 and the seal 28, namely the area 36, is filled with grease so as to provide desired lubrication and a further barrier to the entrance of undesired particles which tend to contaminate the seals 28 and 34. A passageway 38, designed to accommodate an ordinary grease gun, may be formed in the ring 24 to allow the area 36 to be properly lubricated.

The housing 2 is mounted adjacent the drum 8 by the supporting frame 4, as shown in FIGURES 1, 4, 5, and 13 and includes a pair of saddles 40 interacting with and accommodating a pair of channel members 42. The supporting frame 4 will be described in greater detail hereinafter, but at this point it is sufficient to understand that the housing 2 is suitably non-rotatably mounted adjacent the drum 8 and is sealed thereto by the means 22 or more precisely by the O-ring seals 28 and 34. This sealing engagement between the housing 2 and the drum 8 assures that no concrete can leak between these members to harden therein and thus prevent or impede free rotation of the drum 8.

The housing 2 has a rear wall 66, a top wall 62, and a bottom wall 64 which merges .into the front wall 29. Essentially, the front wall 29 includesthe ring 24 as a part thereof, with the interior of such ring forming a forward opening for the housing 2. The rear wall 60 of the housing has an opening 66 along its upper portion which forms part of the chute 3, or alternatively, through which the chute 3 extends. The hopper chute 3 may be a separate member engageable with the housing 2, or it may be integrally attached to the housing 2. As shown in FIGURE 5, the chute 3 terminates in a forward wall 79 which is disposed within the opening 66 and which has another opening 71 beneath it. The opening 71 is closable by a sealing valve means generally designated 72 which includes a sealing face plate 74 and a pivotal support arrangement formed by an elongated slot 76 which accommodates a shaft 78 and allows it some sliding play to permit a locking operation to be now described.

The support arrangement permits the sealing plate 74 to be movable about the pivot shaft 78 under the action of a linkage 80 which includes a first link 82, a second link 84 and a third link 86. The links 82 and 84 are freely coupled together about a pivot joint 88, and similarly, the links 84 and 86 are freely coupled together about a pivot joint 90. The link 86, however, has a terminal end which is pivotal about a fixed shaft 92. The shaft 92 carries a handle 94 thereon which handle is movable between a closed position as indicated in solid lines and an open position as indicated in dashed lines, both in FIGURE 5. When the handle 94 is moved to its open position, the sealing plate '74 of the valve member 72 assumes the dotted line position shown, whereat it is disposed inwardly of the drum 8. When the handle 94 is in its closed position, as shown in solid lines, the sealing plate 74 is in engagement with the terminal edges of the forward wall 76 and a tapered lowered chute wall 96 to thus close the opening 71 and thereby effect a seal. The linkage 80 is such that the pivot points 90, 92 and 88 are aligned with the pivot point moving over dead center position to effect a lock of the valve 72 in the closed position-i.e., with the sealing plate 74 abutting the edges surrounding the chute opening 71. It is important that the sealing plate 74 be capable of firmly and effectively sealing off the opening in the chute '3, since, when air is subsequently introduced into the drum 3, such air must be prevented from back leakage through the hopper chute 3 if positive pressurized feeding of the mixed concrete is to be properly effected.

In order to introduce into the drum 8, the ingredients which must be mixed together to form the concrete, the valve means 72 is opened :bymoving the handle 94 to its open position, as shown in dashed lines in FIGURE 5, thus causing the valve member 74 to pivot to its open position, also shown in dashed lines. When the valve means 72 assumes its open position, the ingredients can feed through the open upper end of the hopper chute 3,- travel down the tapering lower wall 96 thereof, continue across a similarly tapering auxiliary wall 102 in the housing 2, and feed into the interior of the drum 8. to be noted that although the wall 102 extends into the interior of the drum 8, it is nevertheless spaced from the walls thereof by a distance in excess of the height of the conventional spiral flights 104 formed on the interior of such walls. Duringand after the filling operation, the drum 8 is rotated in one direction to combine and mix the ingredients introduced thereinto. As is conventional, during such rotation the flights feed the ingredients toward the enlarged center of the mixing drum. However, when it is desired to discharge the mixed concrete, whether by pressure or by gravity, the direction of drum rotation is reversed and the flights 1G4 feed the the wall 102 and into the housing 2, to be discharged through the outlet means in a manner to be presently described.

As was previously indicated, the supporting frame 4 maintains the housing 2 in a non-rotatable disposition while the means 22 sea-ls the housing to the mixing drum 8. Since the mixing drum 8 rotates about its own axis, a relative rotation occurs at the interface of the housing 2 and the drum 8. In addition to that portion 22 which seals the housing and the drum together, it is also necessary to provide a means for coupling the housing and drum together and, to that end, the means 6 also includes a plurality of roller means which not only provide such a coupling and permit such relative rotation but which also prevent any undesired play or movement from occurring, either transversely or axially of the drum 8. Generally, such means 6 includes roller means generally designated 114 which prevents axial movement between the housing and the drum and roller means generally designated 116 which prevents any lateral or transverse movement between the housing 2 andthe drum 8. In the preferred embodiment, an additional roller means generally designated 130 is used in conjunction with the roller means 116. All of the roller means cooperate in engagement with the hub 14 and more precisely, with the base wall 16 thereof.

As shown in FIGURES 8 and 9, the roller means 116 each include an upstanding bracket member 118 and a roller 121) mountedon the bracket member 118 by a shaft 122 having a threaded end which receives a nut 124. The roller 120, as shown in FIGURE 9, engages the periphery of the base wall 16 of the hub 14. Preferably three basic roller means 116 are incorporated, spaced approximately 120 apart With one such roller means being at the base of the apparatus, and with the remaining two such roller means being above the horizontal center of the apparatus. In addition, the preferred embodiment contemplates using an additional roller means generally designated 130 and shown in FIGURES 10 and 11. This roller means 130 includes a pair of spaced rollers 132 and 134 mounted on a bracket 136 by means 'of transversely extending shafts 138 which receive nuts 140 on one end and are enlarged into heads 142 at their other end. The bracket 136, however, is itself pivotally mounted as about a pin shaft 144 which passes through an elongated slot 146 which permits slight play of the pin shaft 144. The pin shaft 144 is supported by a further bracket 148 fixed to the It is housing 2. With this arrangement, the bracket 136 can pivot in operation and the position of the bracket 136 with respect to the pin shaft 144 can be adjusted by means of a set screw 149 which projects into the slot 146 and which can be suitably adjusted to assure that the respective rollers 132 and 134 will engage essentially the top periphery of the base wall 16 of the hub 14.

The roller means 114, as shown in FIGURES 6 and 7 each include a bifurcated bracket formed by a pair of spaced legs 150 which depend either integrally from the ring 24 or which are suitably aflixed thereto, as by welding. A cross-bar 152 extends between the legs 150 substantially midway along their length, and above this crosscar, a first rol1er 154 is disposed. A spacer 156 is mounted between the roller and the ring 24, and a stub shaft 158 extends centrally through the cross-bar, roller and spacer,

- to thereby pivotally mount the roller with its face in engagement with the outer face of the hub 14. Disposed beneath the cross-bar 152 is a plate member 160 carrying,

a pivotally mounted second roller 162 at one end thereof. The second roller- 162 is engageable with the inner face of the base wall 16 of the hub 14. The plate 160 is fixed in position by a cam shaft 164 passing through aligned apertures in the respective spaced legs 150. When the cam shaft is rotated by an attached handle 166 to an engaged position, with the handle substantially parallel to the legs 150, the plate member 160 is tightly pressed against the underside of the cross-bar 152 and is thus retained in position with the roller 162 engaging the hub 14. When the cam shaft 164 is rotated to a disengaged position, with the handle 166 substantially perpendicular to the legs 150, the plate member 160- is loosely disposed between the cross-bar and the cam shaft and can be easily manually removed. I

When the cam shaft is disengaged, and the plate member 160 is manually removed, the entire attachment is free to move rearwardly or axially away from the drum 8 since the housing 2 is supported only by its support frame 4 and by the roller means 116 and engaging the periphery of the hub base wall 16. The rollers 152 contact the rear face of the hub base wall and can move freely rearwardly thereof. As can be seen from FIGURE 4, preferably four such roller means 114 are employed, being disposed in equally spaced relation about the periphery of housing 2. It will be apparent that the handles 166- can be quickly and easily turned by hand to loosen the mounting of the plate members and permit them to be manually removed. When this removal has been effected, the housing 2 can be moved rearwardly to separate the ring 24 from the hub 14 to permit cleaning and relubrication of the seals 28 and 44 and the spaces surrounding and between such seals.

The ability to perform such rearward movement to separate the housing from the drum is particularly significant in the present equipment since such equipment is designed for mixing and delivering concrete, which, as is well known, tends to harden readily. It is therefore important to remove any caked concrete from the sealing means 22 to assure that the equipment will function properly with the sealing components performing their desired sealing and the drum 8 free to rotate relatively to the housing 2.

Notwithstanding the fact that the housing 2 is free for movement rearwardly of the drum 8 once the plates 160 have been removed, the weight and bulk of the housing, plus its need for maintaining accurate alignment for future recoupling, prevent the housing from being 'merely manually moved by a pushing or a pulling force applied to it. Instead, a positive rearward drive means is provided for effecting the uncoupling movement and this drive means is mounted within the supporting frame 4 by utilizing a rack and pinion mechanism to eifectrelative movement of the frame members 40 and 42. As can be seen in FIGURES 1, 4, 5 and 12 through 15, the channels 42 form a generally U-shaped arrangement surrounding the attachment, with the legs of the U-shape being disposed on opposite sides of the mixing drum 8. Suitable means such as bolts 196 attach the channels to plates 198 which form a part of a frame 2R0 extending from the bed of the truck 1 and surrounding the drum 8. A saddle 4th is disposed 011 the interior of each channel 42 and plates 201 connect the saddles to opposite sides of the housing 2. In the space between each saddle 4t) and channel 4 2, a rack 202 and a pinion gear 204 are mounted and are operable to move the saddles 4t) and the interconnected housing 2 relative to the drum 8.

Eachrack 262 is attached to its associated saddle 40 by a bolt 205, and the pinions 204 which engage the racks 202 are mounted on a common shaft 2&8 which extends completely across and through the oppositely disposed channels 42. On the outer ends of the shaft 208, which extend beyond the channels 42, handle wheels 210 are suitably mounted. The pimons 204 may be maintained at their proper places along the shaft 208 by shrink fitting, collars, or other like expedients. A guide 206 is afiixed to the inner face of each channel leg 42 and is provided with a downwardly extending flange portion 212 which overlies the inner face of the rack 202 and maintains it in proper alignment, with the lower teeth on the rack 232 ongaging the teeth on the associated pinion 204.

In ordinary operation when the housing 2 is coupled to the drum 8, the handle wheels 210 are immovable since the rollers 154 engage one face of the hub base wall 16 and prevent movement toward the drum and the rollers 162 engage the opposite face of the hub base wall 16 and prevent movement away from the drum 8. However, once the plate members 160 and their attached rollers 162 have been removed in the manner previously described, the handle wheels 210 can be rotated in one direction to move the housing 2 rearwardly and thus uncouple it from the drum 8. This rearward movement is eifectuated by the pinions 204 causing the racks 202 to move rearwardly, and since the racks are secured to the saddles 49, such saddles and the interconnected housing 2 are carried rearwardly. Once the required cleaning and relubrication of the means 22 has been accomplished, the handles 210 are rotated in the opposite direction to move the housing 2 toward the drum 8 until the rollers 154 contact the base wall 16 of the hub 14. At this point, the plate members 160 can be reinstalled and properly maintained in position by operation of the handles 166 and their associated cam shafts 164, and the result is that the housing 2 is once more coupled to the mixing drum 8.

When the housing 2 is properly coupled in position, and when the drum 8 has received and mixed the ingredie'nts for the concrete, the valve means 72 in the hopper is closed and the equipment is' ready to discharge the mixed concrete. When such concrete is to be delivered under pressure, some suitable means must be provided for pressurizing the interior of the drum 8. To this end, an air compressor 240 is provided on the bed of the truck 1 alongside the drum 8. A hose or pipe 242 connects the compressor 240 to an opening 244 in the housing 2 to deliver air under pressure from the compressor through the housing 2 and into the interior of the mixing drum 8. A conventional check valve, not shown, may be provided to prevent any air having entrained dirt from flowing back through the line 242 to the compressor A conventional safety relief valve 246, both manually and automatically operable, can be provided adjacent the opening 24-4 to prevent the pressure within the drum 8 from building up too great a magnitude.

It is intended that the present equipment deliver compressed air from the compressor 240 to the drum 8 under uniform pressure. Therefore, in order to vary the discharge flow rate of the mixed concrete, the operator must vary the speed of rotation of the drum 8. However, if, as will be presently described, the mixed concrete is discharging into a conduit means from which 8. it exits at a distance quite remote from the truck 1, an operator stationed at the truck is unable to see the flow rate of the concrete and hence is unable to make any required drum speed adjustments. Toovercome this problem, means is provided for permitting the operator to view the interior of the housing 2 to observe the rate of flow of the discharging concrete. To this end, a ladder 252 is attached to the side of the equipment, as shown in FIGURE 1, and a window means or peep hole is provided along the upper portion of the periphery of the housing 2. The peep hole is in the form of an outwardly projecting mounting boss 254 having a window 256, preferably unbreakable, mounted therein in an orientation to permit observation of the outlet in the base of the housing. By properly positioning himself on the ladder 252, an operator can look through the window 256 and see the base of the housing 2 and the outlet therefrom. If, in such a position, the operator sees that an excess of concrete is discharging from the outlet, he reduces the rotational speed of the drum 8, whereas if he sees that more concrete is required, he increases the drum rotational speed.

Turning now to the outlet means 10 by which the mixed concrete is discharged from the present equipment, it can be observed from FIGURE 5 that, within the bottom wall 64 of the housing 2 a preferably circular outlet opening 258 is formed. A coupling elbow 260 is mounted within the opening 258, preferably swivelably, and depends therefrom to permit flow into a conduit means generally designated 262. The purpose of the conduit means 262 is to permit long distance delivery of the mixed concrete as it is discharged under pressure. The conduit means will be discussed in greater detail hereinafter, but for present purposes, it is sufficient to state that such conduit means includes flexible lengths of tubing 264 and fixed lengths of tubing 266, as shown in FIGURES 1 and 2.

Also included in the outlet means 10 is a closure assembly generally designated 270 which is designed to be applied in overlying relationship to the coupling 258 to receive flow therefrom. As can be seen from FIGURES 1, 3 and 4, the closure assembly 270 is generally L-shaped and of rectangular contour having an upstanding or vertical wall 270 adapted to be juxtaposed to the front wall 60 of the housing 2 and also having a base or horizontal wall 272 adapted to be juxtaposed to the housing bottom wall 64. A depending wall means 276 tapers or diverges inwardly as it extends downward from the wall 272, and the coupling 258 extends into this tapering wall means. At the lower end of the tapering wall means 276, a collar 278 is provided, and this collar serves as a means for securing or attaching the conduit means 262.

It will be noted from FIGURE 1, and more particularly from FIGURE 5, that the closure assembly 270 and hence the interconnected conduit means 262 is not located centrally of the base of the rear wall 65) on the housing 2, but rather is offset slightly to the right thereof, as shown. The reason for this offset relation is that when the drum 8 is discharging concrete, its rotational direction is clockwise, when viewed from the orientation of FIGURE 5, and hence the concrete feeds down the right side of the housing 2. Thus, to make the concrete delivery as efiicient as possible, the closure assembly is disposed toward the right side of the housing to receive the concrete with as little obstruction to gravity flow as is possible.

The closure assembly 270 is detachable from the housing 2, and is preferably fastened thereto by a quick detachment mechanism 280, as shown in FIGURE 4, although it may be attached by bolts 282, as shown in FIGURE 1. The mechanism 280 can be of the cam type to facilitate quick detachment of the closure assembly 270, and when the assembly is detached, the housing 2 has the outlet means 10 merely at the base thereof. The purpose for detaching the closure assembly 270 is to remove the conduit means 262 from attachment with 9 the housing 2 in order to maximize the conventional or gravity output of the equipment.

Because of the restricted size or diameter of the conduit means 262, the flow rate of concrete therethrough is.

somewhat less than could be achieved by merely allowing the concrete to discharge under gravity from the opening 258 inthe base of the housing 2. Also, if it is desired to feed concrete. to a source immediately adjacent the truck 1, use of the conduit means 262 may actually be more of a hindrance than a help. Accordingly, when the concrete is to be discharged conventionally by gravity, and when a maximum flow rate is desired or when the discharge is to a source near the truck, the closure assembly 270 may be detached to remove the conduit means 262 as shown in FIGURE 16. In such an instance, a conventional chute 282 (FIG. 1), of either one piece or of interfitting parts, may be disposed beneath the outlet opening 258 (FIG. 5).

. As was previously mentioned, concrete has a propensity to quickly .harden or set, and after such concrete has been discharged through the conduit means 262, it is necessary to clean or flush the interior thereof in order to prevent excess concrete from hardening on the interior walls of the tubing and thereby reducing the effective diameter of the tubing and also making such tubing stiff and diflicult to move. Such a flushing or washing operation is also helpful in cleaning the interior of the housing 2 to prevent excess concrete from hardening therein. To efiect such a flushing operation, a valve means generally designated 300 is incorporated into the outlet means 10.

As can be seen from FIGURE 5, and more fullyfrom FIGURES 17 and 18, the valve means 300 includes a valve member 302 carried at the base of a valve support rod 304 and adapted to close off the outlet opening 258 in the base Wall 64 of the housing 2. A link 306 is coupled at one of its ends to approximately the center of the valve support rod 304 and is coupled at its other end to a pivot mounting 308 on the interior walls of the housing 2. Another link 310 is pivotally coupled to the upper end of the rod 304 and is also coupled, at its other end, to a shaft 312 which is journaled in mounting relation within a quadrant plate to be presently described. A handle 314 is affixed to the shaft 312 and the handle can be manually operated to move the valve between a closed position as shown in FIGURE 17 and an open position as shown in FIGURE 18.

When the equipment is dispensing or discharging concrete, the valve means is maintained in its open position to allow the concrete to discharge through the outlet opening 258 in the housing 2. However, when it is desired to clean or flush the equipment, the valve means 300 is closed and water is supplied through a pipe 348, as shown in FIGURE 1, into an auxiliary water line 350 located within the housing 2. The line 350 is slightly angled downward and toward the right, as shown in FIGURE 5, to assure that Water exiting from its. outlet end 352 will flow down the right side of the housing walls which, as previously described, receives the brunt of the downward flow of discharging concrete. Since the valve means 300 is closed and the valve member 302 is sealing off the outlet opening 258, the water will build up in the housing 2. When it reaches its desired level, which the operator can determine by visual observation through the window 254, the handle 314 is manually lifted to open the valve means 300 and allow the water to drain out of the housing andthrough the conduit means 262. The handle is then released and the valve means closes again to allow the housing to fill again with water. Thus, by continuous intermittent operation of the handle 314, separate-charges or surges of water can be fed through the conduit means 262 to cleanse the interior thereof. During such a cleaning or flushing operation, compressed air is. continuously supplied in the manner previously described to thus cause the charges of water to positively 10 V feed through the conduit means in advance of a pressure head of compressed air.

Since the valve means 300 is to be intermittently or reciprocably operated, it may be desirable to provide means for adjusting the length of the stroke between the open and closed valve position. To this end, a quadrant plate 400 is incorporated into the valve means 300. The quadrant plate is a sectorially-shaped member having a plurality of spaced apertures 402 located along its curved periphery. The apertures 402 are designed to receive a-p'rojecting pin 404 which extends from the underside of the handle 314, as shown in FIGURE 5. The handle 314- is freely journaled on the shaft 312 and is biased against the plate 400 by a compression spring 406 disposed about the shaft 312 and extending between its enlarged head end 408 and the plate 400. Such a mounting arrangement assures that the handle 314 is positively coupled to the shaft 312 only when the pin 404 is extending through a plate aperture 402, and hence the valve means 300 cannot operate without the quadrant plate 400 being coupled to the handle 314. The quadrant plate 400 limits the movement of the handle and thereby limits the stroke of the valve means 300. Changing the location of the pin 404 in the quadrant plate by moving it to a different aperture 402 can either shorten or lengthen the stroke of the valve means.

Turning now to the details of the conduit means 262, reference is made to FIGURES 1 and 2. which show that the rigid or fixed lengths of tubing 266- and the flexible lengths of tubing 264 are suitably interconnected to one another by collars of similar coupling members. To

provide additional support for the flexible lengths 264, a

double-leg pivoted bracket 420 can be disposed on opposite sides of each length, with the ends of the bracket legs connecting to the ends of the length of tubing. In order to provide means for lifting and positioning of the conduit means 262, wires or ropes 424 are attached to spaced lengths along the conduit means and these wires pass over freely movable pulleys or sheaves 426 and are attached to manually operable'winding winch means 428. By turning the operating handle 430 on a winch 428, the operator is able to selectively raise or lower the conduit means 262.

However, it can be seen that the maximum height to which the conduit means can be elevated is that at which the pulleys 426 are located. It is, therefore, desirable to provide some means for raising the height of the pulleys 426 from their position as shown in FIGURE 1 to their position as shown in FIGURE 2 and to this end, an auxiliary frame is provided. The auxiliary frame includes several struts 432 extending rearwardly from the frame member 200 which surrounds the mixing drum 8. At the outer end 434 where these struts are pinned or fastened together, a generally U-shaped brace 436 is pivotally mounted with an end of each of its legs pivoted at the ends 434. On the brace crossmember which extends between its legs, the pulleys 426 are freely mounted. The pulleys themselves can be connected to the brace 436 by wires so they may be lowered therefrom or raised into contact therewith while still being free to pivot. A telescoping lifting and lowering mechanism 440 is disposed above the housing 2 and extending centrally between the frame 200 and the brace 436. Normally, the brace 436 is folded downward since its height when extending above the housing may make the truck 1 too high to pass beneath the clearance on bridges, underpasses, and tunnels 'which it might encounted. However, when it is desired to elevate the pulleys 426, the mechanism 440 can be operated, either manually or automatically, to raise the brace 436 to the position of FIGURE 2 and hence to elevate the pulleys affixed thereto.

As has been previously described, it is necessary for the operator to visually observe the interior of the housing 2, both to determine the discharge flow rate of the cement and to determine the height of the water level during a flushing operation, and the peep hole and window 254 have been provided to permit such visual observation. However, due to the fact that the outlet opening 258 is generally sealed by the closure assembly 270, the interior of the housing 2 is sealed from light except for that entering through the small window 254. Moreover, when the operator places his face before the window 254, he blocks out even what little light ordinarily shines through that window. Therefore, in order to illuminate the interior of the housing for observation thereof, a light 5% is positioned on the left side wall of the housing as seen in FIGURE 4. Since, as was previously described, the clockwise drum rotation during discharge causes the concrete to feed along the right side wall of the housing, very little, if any, concrete will contact the light 500. If desired, a transparent envelope, not shown, may be placed over the light 500 to render it waterproof so it cannot be affected during the flushing operation.

Also, because of the temperature differential which exists between the interior of the housing 2 and the ambient atmosphere due to the presence of the mixed concrete, the inner face of the window 254 tends to become fogged or clouded with condensation which prevents viewing therethrough. To eliminate this problem, a manually operated wind-shield wiper 502 is supported interiorly of the peep hole with the blade 564 thereof in engagement with the interior of the window 256. A blade support mechanism 536 pivotally mounts the blade 564 and is operable through an externally extending handle 50? whereby the blade 504 may be moved back and forth across the window 256 to clear any condensation therefrom.

The foregoing matter has set forth, in detail, the componential make-up of the concrete mixing equipment and the attachment therefor. To fully understand the sig nificance of such equipment, the operation thereof will be set forth hereinafter.

To make or mix the concrete, the handle 94 is moved to a position to open the valve means 72, and the concrete ingredients are fed into the hopper chute 3 from whence they pass into the mixing drum 8. The drum is rotated in one direction, counter-clockwise as viewed in FIGURE 4, and the flights 104 feed the ingredients inwardly toward the center of the drum where they are mixed to form the concrete. When the concrete has been mixed sufficiently and it is desired to discharge it, the direction of drum rotation is reversed, to a clockwise direction as viewed in FIGURE 4, and the flights 104 feed the mixed concrete. toward the outlet of the drum, beneath the auxiliary wall 162, and into the interior of the housing 2.

Normally, the closure assembly 270 and thus the conduit means 262 are attached to the housing 2 and the valve means 300 within the housing is open. The winches 4-28, andif need be the telescoping mechanism 440, are operated to accurately position the conduit means 262. The handle 94 is moved to close the valve means 72 and to thus seal off the hopper chute. The air compressor 240 is started and compressed air therefrom is delivered to the interior of the drum 8 and thus into the interior of the housing 2. The compressed air serves as a fluid conveyor to discharge the mixed concrete, under pressure, from the drum 8, through the housing 2, and through the conduit means 262 to its desired location. As such pressurized dispensing or discharging occurs, the operator stations himself on the ladder 252 and visually examines the interior of the housing 2 through the window 254. If the window is fogged, he clears it with the wiper mechanism 502. The light 500 illuminates the interior of the housing 2 and permits the operator to see the outlet opening 258 in the base thereof. If the operator sees that the concrete is not discharging at a fast enough rate, he increases the rotational speed of the drum 8, and similarly if he sees that the concrete is discharging too quickly and .12 an excess is building up at the outlet, he decreases the rotational speed of the drum 8.

After the concrete dispensing operation has been completed, the operator leaves the air compressor 240 running and closes the valve means 300. He then introduces water through the pipe 348 into the interior of the housing 2 and allows it to build up to a desired level, which can be seen through the window 254. If, during this water-filling operation, the air pressure within the drum becomes too great, the safety relief valve 246 opens to decrease the pressure back to a safe level. When the housing 2 has filled with water to the desired level, the operator lifts the handle 314 and opens the valve means 300, thus allowing the water to drain from the housing and to pass through the conduit means 262 in advance of a pressure head of compressed air. The operator may then close the valve means 3430 again and repeat the foregoing operation until several surges of water have passed through the conduit means 262 and have thoroughly cleansed the interior thereof.

As an alternative operation, it may sometimes be desirable to discharge the mixed concrete by conventional gravity flow. In such an instance, the mechanisms 280 are released and the closure assembly 270 with its interconnected conduit means 262 is removed from beneath the housing outlet opening 258. Then, when the direction of drum rotation is reversed to feed the mixedconcrete out of the drum, the concrete empties, by gravity through the outlet opening 258 and the coupling 260 depending therefrom. It will be understood that the housing outlet opening 258 is of a substantially larger diameter than the discharge opening of the closure assembly 276. Such gravitational delivery can be into a chute such as 282 in FIGURE 1, which may be cranked into position beneath the coupling 260 by a winch 520 having a manually operable handle 522, or it may be merely into buckets or wheelbarrows.

When a number of dispensing operations have been performed, either by gravity or under pressure, it is necessary to clean the interface between the drum 8 and the housing 2 to remove any cake concrete which might have accumulated therein. To accomplish this, the handles 166 on the roller means 114 are opened or moved to allow the plate members 160, with their attached rollers 162, to be manually-removed. When these plate members have been removed, the handle wheel 210 is turned to operate the rack 202 and pinion 204 mechanism in the supporting frame 4, and to thus move the housing 2 rearwardly away from the drum 8 to an uncoupled position. At this uncoupled position, the sealing means 22 may be cleaned and relubricated and, if necessary, now O-ring seals 28 and 34 may be inserted. The handle Wheel 210 is then turned in the opposite direction to recouple the housing 2 :and the drum 8, and the plate members 166 are reinserted into their proper positions and retained therein by their associated cam shafts 164.

After reading the foregoing detailed description, it should be apparent that the objects set forth at the outset of this specification have been successfully achieved, accordingly,

What is claimed is:

1. Apparatus for mixing and dispensing material comprising:

(a) a rotatable mixing drum having an open end;

(b) an attachment juxtaposed to said open end for introducing material into and receiving material from said drum;

(c) said attachment including a housing having an outlet means at its base and means for sealingly engaging said housing peripherally of said opened end of said drum;

(d) said attachment also including a hopper chute in engagement with said housing for introducing material therethrough and into said drum through its open end to be mixed therein;

(e) Supporting frame means extending outwardly of said drum and supporting said attachment for movement thereof toward and away from said drum;

(f) rackand pinion means on said supporting frame means for moving said attachment toward and away from said drum; and,

(g) selectively operable means for pressurizing the interior of said drum to dispense the mixed material through said outlet means. 7

2. Apparatus for mixing and dispensing material as defined in claim 1 wherein said supporting frame means comprises a supporting frame surrounding said attachment.

3. Apparatus as defined in claim 1 wherein said drum carries mixing and conveying means therein whereby when said drurn'is rotated in one direction, material introduced therein through said hopper chute is conveyed from said hopper chute and mixed, and when said drum is rotated in the opposite direction, the mixed material is conveyed into said housing and dispensed through said outletmeans.

4. Apparatus as defined in claim 1 wherein said means for sealingly engaging said housing peripherally of said opened end of said drum comprises at least one O-ring seal and mounting means therefor to permit said drum to rotate relatively to said attachment. 5. Apparatus as defined in claim 1 wherein said seleclivery line for introducing compressed air into said drum, wherein said outlet means includes a removable assembly coupled to the base of said housing, and wherein said attachment includes sealing meanscooperating with said hopper chute to selectively close the same during pressurizing of said drum to maintain the pressure therein. 6. Apparatus as defined in claim 1 wherein said attachment includes valve means in said housing adapted to close said outlet means, conduit means coupled with said outlet means to convey discharge mixed material therefrom to a distant location; means for introducing water into said housing for cleaning the interior thereof and the interior of said conduit means, window means in said housing to permit visual observation of the interior thereof, light means in said housing toillumina-te the interior thereof so that the interior of said outlet means can be observed through said window means, and means for removing condensation from said window means to facilitate viewing therethrough.

t 7. Concrete mixing and dispensing equipment adapted to be mounted on the bed of a truck and comprising:

a rotatable mixing drum having shaped flights on the interior walls thereof and having one normally open end;

an attachment adapted to be coupled to said drum at its open end;

said attachment including a housing having an outlet opening at its base;

means for sealingly coupling said housing to said drum open end to permit relative rotation between said drum and housing and yet to sealingly engage said drum and housing together;

said attachment also including a hopper chute engaged with said housing and communicating there-through with said drum to introduce concrete forming ingredients thereinto;

sealing means cooperating with said hopper chute and being operable to open and close said chute whereby material can be introduced into said drum through said chute and said housing when said sealing means opens said chute and saiddrum and housing can be closed to the surrounding atmosphere through said chute when said sealing means closes said chute;

a closure assembly removably mounted on said housing in juxtaposition to said outlet opening;

said closure assembly including an elongated conduit means manipulable'to reach locations remote from said truck;

a supporting frame movably mounting said housing .tively operable means includes an air compressor and a deadjacent said drum and being operative, when said coupling means are suitably disengaged, to move said housing relatively to said drum between a coupled and an uncoupled position;

window means formed in said housing to permit visual observation of the interior thereof;

said window means being oriented to permit visual interior observation of said outlet opening; and

selectively operable pressurizing means for pressurizing the interior of said drum to facilitate dispensing of the mixed concrete therefrom;

said drum being adapted to be rotated in one direction in which said flights direct the ingredients introduced through said hopper chute toward the interior of said drum to mix said ingredients and thereby formmixed concrete;

said drum also being adapted to be rotated in the opposite direction in which said flights feed said mixed concrete out of said drum and into said housing for dispensing thereof;

said pressurizing means being operable, when said closure assembly is mounted on said housing, to dispense said mixed concrete through said conduit means under pressure;

said equipment also being operable, when said closure assembly is dismounted from said housing, to dispense said mixed concrete through said outlet opening by gravity flow;

8. Concrete mixing and dispensing equipment as defined in claim 7 wherein the means for sealingly coupling said housing and said drum includes:

a peripheral flange'on said drum surrounding its open a hub member secured to said peripheral flange and including a base wall extending parallel to and beyond said flange and a ring member extending axially away from said drum;

sealing means aflixed to said housing and accommodating at least two O-ring seals, one of which sealngly engages said base wall and one of which sealingly engages said ring member; I 1

a first set of roller means secured to said sealing means and engageable with the periphery of said base wall to permit rotary movement between said housing and drum but to prevent any transverse or lateral movement therebetween; and

a second set of roller means secured to said sealing means and engageable With the opposite surfaces of said base wall to couple said housing and drum together, to permit rotary movement therebet-ween, but

to prevent axial movement therebetween along the axis of said drum.

9. Concrete mixing and dispensing equipment as defined lIl claim 8 wherein at least one roller means of said first set is adjustably mounted to be moved toward or away from the periphery of said base w-all. '10. Concrete mixing and dispensing equipment as defined in claim 8 wherein said second set of roller means includes a plurality of rollers bearing against the housing side of said base wall and a plurality of rollers bearin against the drum side of said base wall. a

11. Concrete mixing and dispensing equipment as defined in claim 10 wherein said rollers which bear against .the drum side of said base wall are mounted on plate rnlerfnbers, each disposed adjacent a manually movable cam said cam shafts being movable to a locking position wherein said plate members are locked in position with said rollers bearing against the drum side of said base wall;

said cam shafts also being movable to an unlocked position wherein said plate members and their associated rollers can be manually removed to uncouple said housing from said drum. 12. Concrete mixing and dispensing equipment as del fined in claim 7 wherein said sealing valve means includes an operating handle, a valve member and a linkage securing said operating handle and said valve member together to move said valve member responsively to the movement of said operating handle.

13. Concrete mixing and dispensing equipment as defined in claim 12 wherein 'said'linkage is movable to an over-dead-center position to lock said valve member in its closed and sealing position.

14. Concrete mixing and dispensing equipment as defined in claim 7 wherein said conduit means includes at least one flexible length of tubing.

15. Concrete mixing and dispensing equipment as defined in claim 14 but further characterized by guide wire means attached to said conduit means, pulley means mounting said guide wire means, and winch means for winding and unwinding said guide wire means to manipulate said conduit means.

16. Concrete mixing and dispensing equipment as defined in claim 15 -wherein said pulley means are mounted on a movable frame secured to said truck.

17. Concrete mixing and dispensing equipment as defined in claim 16 but further characterized by a telescoping mechanism connected to said movable frame to elevate it to a height above said drum and said attachment.

'18. Concrete mixing and dispensing equipment as defined in claim 7 wherein said supporting frame includes:

a channel member disposed in spaced relation to each side of said housing;

a saddle member'affixed to each side of said housing and engaged with said channel member for slidable movement therealong;

a rack member aflixed to each saddle member;

a shaft extending between said spaced members;

a pinion gear mounted on said shaft beneath each rack member; and

at least one handle means on said shaft to facilitate manual rotation thereof whereby said pinions will reciprocate said rack members to move said saddle members and said interconnected housing.

19. Concrete mixing and dispensing equipment as defined in claim 7 wherein the orientation of said window means is adjacent the top of said housing to permit downward viewing to see said outlet opening.

20. Concrete mixing and dispensing equipment as defined in claim 19 but further characterized by :a ladder adjacent said window means to permit an observer to look downward through said Window means.

21. Concrete mixing and dispensing equipment as defined in claim 7 wherein said window means is provided with a manually operable wiping means for cleaning any condensation therefrom.

22. Concrete mixing and dispensing equipment as defined in claim 7 but further characterized by a light on the interior of said housing for illumination thereof.

23. Concrete mixing and dispensing equipment as defined in claim 7 wherein said pressurizing means includes an air compressor and a delivery line communicating with said housing means for introducing compressed air therethrough and into said drum for pressurizing the interior thereof.

24. Concrete mixing and dispensing equipment as defined in claim 23 but further characterized by a safety relief valve in said delivery line to prevent excess pressurization of said drum. 25. Concrete mixing and dispensing equipment as defined in claim 7 wherein said housing includes an internally mounted, manually operable, pivotal valve means having a valve member adapted to close off said outlet opening.

26. Concrete mixing and dispensing equipment as defined in claim 25 wherein said valve means includes an operating handle exteriorly mounted on said housing and connected to said valve member and wherein said handle channel is cooperatively engageable with a stroke adjusting plate to alter the stroke of said valve member in moving between its open and its closed position.

27. Concrete mixing and dispensing equipment as defined in claim 25 but further characterized by means for introducing water into said housing for cleansing the interior thereof and, when said pivotal valve means is opened, for flowing through said conduit means for flushing out any excess concrete adhering to its walls.

28. For use in combination with a ready-mix concrete truck having an open-ended rotatable mixing drum mounted thereon, with said mixing drum having a peripheral flange surrounding its open end; a dispensing attachment comprising:

a non-rotatable hollow housing having an inlet opening for communication with the open end of said drum and an outlet opening at its base;

coupling means for securing said housing to said drum,

said coupling means including a hub member having a base wall secured to said drum peripheral flange and a ring member extending toward said housing inlet, said base wall having its periphery extending beyond the terminus of said peripheral flange, a first set of roller means engageable with said base wall peripherally to prevent lateral movement between said housing and said drum, and a second set of roller means engageable with the opposite sides of said base wall to normally couple said housing to said drum and to prevent separation thereof;

sealing means for sealing said housing and said drum together in a leakproof manner;

a hopper chute secured to said housing and adapted to introduce concrete ingredients through said housing inlet opening and into said drum; and

means for selectively closing said hopper chute so all concrete dispensed from said drum will discharge through said outlet opening.

29. A dispensing attachment as defined in claim 28 wherein at least one roller means of said first set includes a pair of rollers mounted on opposite ends of a pivotally mounted plate, with the pivotal mounting point of said plate being adjustable toward and away from the periphery of said base wall.

30. A dispensing attachment as defined in claim 28 wherein at least one roller means of said first set includes a plurality of spaced roller members rotatably engaging the base wall on the housing side thereof and another plurality of spaced rollers rotatably engaging the base wall on the drum side thereof.

31. A dispensing attachment as defined in claim 30 wherein said rollers engaging the drum side of said base wall include a mounting means comprising:

a plurality of plate members, each having one roller mounted at one end thereof;

a rotatable cam shaft dispose-d beneath each of said plate members; and

an operating handle secured to each cam shaft;

said operating handles being manually operable to tightly engage said cam shafts against their associated plate members to thus prevent movement of said plate members;

said operating handles also being manually operable to move said cam shafts into loose engagement with their associated plate members whereby said plate members and their attached rollers can be manually removed to thus permit said housing to be uncoupled from said drum.

32. A dispensing attachment as defined in claim 28 wherein said sealing means includes a supporting ring attached to said housing and juxtaposed to said hub member and accommodating at least two O-ring seals, one of which engages sealingly against said base Wall and one of which engages sealingly against said ring member.

33. A dispensing attachment as defined in claim 28 wherein said hopper chute has a lower wall having a taper extending inwardly toward said inlet opening and downwardly toward said outlet opening and wherein said housing further has an auxiliary Wall extending through said inlet opening and into said drum, said auxiliary wall having a taper substantially equal to that of said hopper chute lower wall whereby ingredients introduced into said hopper chute slide down its lower wall, over said housing auxiliary wall and into said drum.

34. A dispensing attachment as defined in claim 28 wherein said hopper chute terminates in an open end disposed within said housing and in substantially parallel planar relation with said housing inlet opening, and wherein said means for selectively closing said hopper chute includes:

a pivotally mounted sealing valve member juxtaposed to said hopper chute open end;

an operating handle mounted exteriorly of said hopper chute; and

linkage interconnecting said operating handle to said valve member whereby said operating handle can be manually moved to pivot said valve member to an open position whereat said hopper chute communicates with said drum and to a closed position Whereat said valve member seals said chute open end.

35. A dispensing attachment as defined in claim 34 wherein said linkage pivots to an over-dead-center position when said handle moves said valve member to a sealing position whereby saidvalve member remains in said sealing position until positively moved therefrom by manual application of force to said operating handle.

36. For use in combination with a ready-mix concrete truck having an open-ended rotatable mixing drum mounted thereon, with said mixing drum having a peripheral flange surrounding its opened end; a dispensing attachment comprising:

(a) a non-rotatable hollow housing having an inlet opening for communication with the opened end of said drum and an outlet opening at its base;

( b) coupling means for securing said housing to said drum;

(c) sealing means for sealing said housing and said drum together in a leak proof manner;

(d) a hopper chute secured to said housing and adapted to introduce concrete ingredients through said housing inlet opening and into said drum;

(e) means for selectively closing said hopper chute so all concrete dispensed from said drum Will discharge through said outlet opening; and,

(f) valve means mounted within said housing adjacent said outlet opening, said valve means including a pivotally mounted valve member juxtaposed to said outlet opening, a valve handle mounted exteriorly of said housing, linkage interconnecting said valve handle to said valve member whereby said handle can be manually moved to pivot said valve member to an open position whereat said outlet opening is uncovered to permit mixed concrete from said drum to discharge therethrough, and to pivot said valve member to a closed position whereat said outlet opening is covered to prevent dispensing therethrough and stroke-adjusting means engageable with said handle to adjust the length of movement between said valve member open and closed positions.

37. A dispensing attachment as defined in claim 28 but further characterized by a closure assembly juxtaposed beneath said outlet opening and secured to said housing by disengagea'ble mounting means which can be manually-disengaged to permit removal of said closure assembly, said. closure assembly including an elongated conduit means for directing the mixed concrete dispensed through said outlet opening to a location spaced away from said housing.

References Cited by the Examiner UNITED STATES PATENTS 1,551,080 8/1925 Welcker 30253 2,316,137 4/1943 Visser 259-16l 2,501,944 3/1950 Jaeger et a1. 259161 2,904,815 9/1959 Mitchell 15-25013 WALTER A. SCHEEL, Primary Examiner.

ROBERT W. JENKINS, Assistant Examiner. 

1. APPARATUS FOR MIXING AND DISPENSING MATERIAL COMPRISING: (A) A ROTATABLE MIXING DRUM HAVING OPEN END; (B) AN ATTACHMENT JUXTAPOSED TO SAID OPEN END FOR INTRODUCING MATERIAL INTO AND RECEIVING MATERIAL FROM SAID DRUM; (C) SAID ATTACHMENT INCLUDING A HOUSING HAVING AN OUTLET MEANS AT ITS BASE AND MEANS FOR SEALINGLY ENGAGING SAID HOUSING PERIPHERALLY OF SAID OPENED END OF SAID DRUM; (D) SAID ATTACHMENT ALSO INCLUDING A HOPPER CHUTE IN ENGAGEMENT WITH SAID HOUSING FOR INTRODUCING MATERAIL THERETHROUGH AND INTO SAID DRUM THROUGH ITS OPEN END TO BE MIXED THEREIN; (E) SUPPORTING FRAME MEANS EXTENDING OUTWARDLY OF SAID DRUM AND SUPPORTING SAID ATTACHMENT FOR MOVEMENT THEREOF TOWARD AND AWAY FROM SAID DRUM; (F) RACK AND PINION MEANS ON SAID SUPPORTING FRAME MEANS FOR MOVING SAID ATTACHMENT AND AWAY FROM SAID DRUM; AND, 